Use a cooler to transport the gelatin. Do not add ice otherwise it may
skew the results. Shoot a steel BB into it at a velocity of 590 fps
± 30 fps (180 m/s ± 9 m/s). It should penetrate 3.35 inches
(8.5 cm). If you don't shoot at the right speed, it will penetrate just a bit
more or less, so a tiny amount of variation is acceptable.